Final answer:
The subject pronoun that you would use to address two professors in Spanish is 'ustedes'.
Step-by-step explanation:
The subject pronoun that you would use to address two professors in Spanish is ustedes. Ustedes is the plural form of the formal second person pronoun 'usted', which is used to show respect or politeness when addressing someone. For example, you can say 'Ustedes son profesores de matemáticas' to address two professors of mathematics.
Learn more about subject pronouns in Spanish